Balloon pen



FIG. 1 is a front elevational view of a balloon pen, the rear elevational view being a mirror image thereof, showing my new design;

FIG. 2 is a left side view thereof, the right side being a mirror image thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a front elevational view of a first alternative arrangement of the balloon pen, the rear elevational view being a mirror image thereof, showing my new design;

FIG. 6 is a left side view thereof, the right side being a mirror image thereof;

FIG. 7 is a top plan view thereof;

FIG. 8 is a bottom plan view thereof;

FIG. 9 is a front elevational view of a second alternative arrangement of the balloon pen, the rear elevational view being a mirror image thereof, showing my new design;

FIG. 10 is a left side view thereof, the right side being a mirror image thereof;

FIG. 11 is a top plan view thereof; and,

FIG. 12 is a bottom plan view thereof. 

The ornamental design for a balloon pen, as shown and described. 